The present invention relates to apparatus and methods for ablating biological tissues. More particularly, the present invention relates to improved ablation devices that are capable of penetrating through bodily organs.
Since their introduction at the end of the 80's, medical ablation devices have become a standard tool for surgeons and electrophysiologists. For example, ablation devices utilizing DC shock, radio frequency (RF) current, ultrasound, microwave, direct heat, cryothermy or lasers have been introduced and employed to various degrees to ablate biological tissues. In some ablation procedures, however, the ablation of the targeted tissues may be difficult because of their location or the presence of physiological obstacle. For example, in some coronary applications where the ablation lines are done epicardially, the epicardium may be covered by layers of fat that can prohibit the lesion formation in the myocardial tissue.
Catheter devices are commonly used to perform the ablation procedure. They are generally inserted into a major vein or artery or through a bodily cavity such as the mouth, urethra, or rectum. These catheters are then guided to a targeted location in the body (e.g., organ) by manipulating the catheter from the insertion point or the natural body's orifice. By way of example, in coronary applications, a catheter is typically inserted tranvenously in the femoral vein and guided to a cardiac chamber to ablate myocardial tissues. Although catheters work well for a number of applications, in many applications it would be desirable to provide an ablation assembly that can be used to position an ablation device during a surgical procedure.